Electric and hybrid electric vehicles, such as locomotives, operate with on-board rechargeable electrical energy storage devices. The energy storage devices may include one or more types of batteries, super-capacitors, utracapacitors, and flywheel systems.
During operation, the energy storage devices experience frequent cycles of periodic charging and discharging. Further, the operating life and performance characteristics of such devices can be affected by the rate and depth of charging/discharging and/or the current level at which charging/discharging occurs. Use of faster and deeper rates and higher current levels during charging/discharging events adversely affect the operating life and storage capacity of an energy storage device. The age of the device, frequency of usage, and temperature of storage are some additional parameters affecting its performance. Reduced performance of electrical energy storage devices in turn may affect the performance and fuel efficiency of the electric vehicle (or hybrid electric vehicle) in which they are used.